The TRIUMPH Programme Trial by Trial: Four Phase 3 Retatrutide Trials, No Published Results

Four phase 3 registrational trials of retatrutide sit under the TRIUMPH banner, enrolling more than 5,800 participants between them, and not one has published a result. Every retatrutide figure in circulation, including 24.2%, comes from somewhere else.

This page maps the programme rather than summarising results, because there are no results to summarise. Retatrutide sits in the weight loss and metabolic peptides category as its most-tested and least-evidenced compound, and what follows sets out what each trial is designed to answer, which questions are covered by two further registered trials outside TRIUMPH, and which circulating numbers can be attributed to any of them. The answer to that last one is none.

What is the TRIUMPH programme, and has any of it reported?

TRIUMPH is a four-trial phase 3 registrational programme for retatrutide enrolling more than 5,800 participants, described in a design paper by Giblin et al. (Diabetes, Obesity and Metabolism, January 2026, PMID 41090431). None of the four has published results. As of 11 August 2026, PubMed contains no phase 3 retatrutide results paper at all, and a search of the New England Journal of Medicine returns four retatrutide records, all from 2023.

The programme's primary endpoints are percent body weight change, apnoea-hypopnoea index, and WOMAC pain. Our source names those three collectively for the programme rather than assigning one to each protocol, so this page does not assign them either — and for the same reason it does not publish a per-trial enrolment figure. More than 5,800 is the programme total; splitting it across four trials would be an invention.

One further limit is worth stating at the top rather than discovering at the bottom. Our sources establish no readout date, primary completion date or publication timeline for any of these six trials, and this article does not estimate one. What can be said with confidence is what each trial is built to answer and what is still unanswered today, which is everything.

Where does the 24.2% figure come from, if not from TRIUMPH?

Retatrutide's 24.2% average weight loss comes from a phase 2 trial: Jastreboff et al., New England Journal of Medicine 2023;389(6):514–526 (PMID 37366315), n=338, 48 weeks, 12 mg dose, double-blind and placebo-controlled. It is not a TRIUMPH result, it is not a phase 3 result, and it predates the registrational programme entirely. The figure is correctly reported almost everywhere; the phase attached to it usually is not.

At least 15% weight loss was achieved by 60–83% of participants across doses, against 2% on placebo. Adverse events were dose-related and gastrointestinal, mostly mild to moderate. The discontinuation rate is not reported in the abstract, and we are not quoting one.

That is a genuinely striking result and it is why retatrutide has the profile it does. It is also 338 people over 48 weeks — a phase 2 trial doing what phase 2 trials do, which is generate a hypothesis worth testing properly. TRIUMPH is the test. It has not reported.

Two other figures circulate and neither belongs to TRIUMPH either. The 28% at 80 weeks figure traces to press reporting of a company statement in May 2026, not to a trial publication, and we could not verify it against a primary source. The 30.3% at 104 weeks figure has no source we could find at all. This site's own retatrutide page previously attributed 24.2% to "Phase 3 TRIUMPH-1" over 80 weeks, with 30.3% at 104 weeks; both figures were wrong and we corrected them.

TRIUMPH-1 and TRIUMPH-2: what does a basket trial with nested protocols test?

TRIUMPH-1 and TRIUMPH-2 are the programme's weight-management basket trials, each carrying nested sleep apnoea and osteoarthritis protocols rather than testing weight alone. That design lets one trial infrastructure answer several indication questions at once, which is why the programme's stated primary endpoints span percent body weight change, apnoea-hypopnoea index and WOMAC pain. Neither trial has published results, so no weight-loss percentage can be attributed to either.

The nested design is the informative part, because it tells you what the sponsor intends to claim. Sleep apnoea and osteoarthritis are not incidental measurements bolted onto a weight trial — they are indications, and running them inside the weight-management protocol is how a programme sets up more than one label at once.

That ambition lands in an already-occupied field on one of the two, and the comparison is instructive. Tirzepatide gained an approved obstructive sleep apnoea indication on 20 December 2024 on the strength of SURMOUNT-OSA (Malhotra et al., NEJM, October 2024, PMID 38912654), two 52-week trials in which the apnoea-hypopnoea index fell by 25.3 events per hour versus 5.3 on placebo in participants not using PAP, and by 29.3 versus 5.5 in those on PAP. Those numbers belong to tirzepatide, not to retatrutide, and they are the benchmark a nested retatrutide sleep apnoea protocol would be read against.

Nothing equivalent exists on the osteoarthritis side, which is what makes that nested protocol the more novel of the two. Neither tirzepatide nor semaglutide carries a knee osteoarthritis indication — tirzepatide's approvals cover type 2 diabetes, chronic weight management and obstructive sleep apnoea, and semaglutide's cover weight management, cardiovascular risk reduction, MASH, type 2 diabetes and chronic kidney disease.

TRIUMPH-3: what does testing retatrutide in obesity with cardiovascular disease add?

TRIUMPH-3 tests retatrutide in obesity with established cardiovascular disease — a population selected for existing cardiac risk rather than for BMI alone. It has not published results. Selecting that population matters because effect sizes and tolerability in a higher-risk, more comorbid group are not automatically those of a healthier trial population, and because it is the population where an obesity drug's cardiovascular story usually begins.

It is worth separating this trial from the outcomes trial described two sections below, because they are frequently conflated. TRIUMPH-3 is a weight-management trial in a cardiovascular population. NCT06383390 is an outcomes trial measuring cardiovascular and kidney events. Weight change in people who have heart disease is a different endpoint from whether fewer of them have heart attacks, and only the second supports a cardiovascular indication.

The precedent for how far apart those two questions sit comes from semaglutide. SELECT enrolled 17,604 patients with obesity and cardiovascular disease but no diabetes, ran roughly 40 months, and found major adverse cardiovascular events of 6.5% versus 8.0% — a hazard ratio of 0.80. That is the shape of evidence a cardiovascular claim requires, and it is not something a weight-management trial in the same population produces.

TRIUMPH-4: what does a knee osteoarthritis trial test that a weight trial does not?

TRIUMPH-4 tests retatrutide in knee osteoarthritis, and WOMAC pain is among the three primary endpoints named for the programme. It has not published results. A pain endpoint asks a different question from a weight endpoint: not how much mass a patient loses, but whether a symptom changes — a patient-reported outcome rather than a measured one, and a different kind of claim from anything the phase 2 trial tested.

This is the most novel of the four trials in indication terms. No approved incretin covered on this platform carries an osteoarthritis indication, so TRIUMPH-4 is not competing against an existing benchmark the way a sleep apnoea protocol is — it is attempting a first.

It is also the trial whose result is hardest to predict from the phase 2 data, because the phase 2 trial measured weight. Nothing in the 338-participant phase 2 record speaks to joint pain, and no figure from it can be carried across to a WOMAC endpoint. Anyone quoting a retatrutide osteoarthritis result today is quoting something that does not exist.

What is the cardiovascular and kidney outcomes trial testing?

NCT06383390 is a cardiovascular and kidney outcomes trial of retatrutide, active and not recruiting, with no published results. Outcomes trials measure events — cardiovascular and renal — rather than percentage weight change, and they are the trials that produce hard risk-reduction claims and cardiovascular indications. It is registered separately from the four TRIUMPH trials, which is why it does not appear in the programme's more-than-5,800-participant total.

The comparators show what this trial is reaching for. Semaglutide's SELECT produced a hazard ratio of 0.80 for major adverse cardiovascular events across 17,604 patients over roughly 40 months, and SUSTAIN-6 produced 0.74 across 3,297 patients with type 2 diabetes — different populations, different baseline risk, different effect sizes, which is exactly why the population a hazard ratio came from has to travel with the number. On the kidney side, semaglutide's chronic kidney disease indication arrived in January 2025.

Tirzepatide makes the contrasting point. Cardiovascular data exist for it and no cardiovascular indication does — its label carries type 2 diabetes, chronic weight management and obstructive sleep apnoea, and nothing cardiac. That gap between "data exist" and "indication exists" is the gap NCT06383390 would have to close for retatrutide, and it has published nothing.

What would the head-to-head against tirzepatide settle?

NCT06662383 is a registered head-to-head trial of retatrutide against tirzepatide, active and not recruiting, with no published results. It is the only trial in this landscape that could establish whether retatrutide actually outperforms the best-evidenced approved incretin, because every current comparison between them is cross-trial: retatrutide's −24.2% is phase 2 in 338 participants over 48 weeks, and tirzepatide's −20.9% is phase 3 in 2,539 over 72 weeks.

There is a precedent for how much a head-to-head can move a settled-seeming number, and it belongs to the same drug class. For three years the field compared tirzepatide with semaglutide by cross-trial arithmetic and estimated a gap of about two percentage points. Then SURMOUNT-5 ran the experiment — 751 adults, 72 weeks, both drugs at maximum tolerated doses — and found −20.2% versus −13.7%, a difference of 6.5 percentage points (P<0.001), roughly three times the cross-trial estimate. The cross-trial direction was right; the magnitude was not.

That cuts both ways for retatrutide, and it is the reason to wait for NCT06662383 rather than to extrapolate from it. Phase 2 results routinely shrink in phase 3: populations broaden, adherence falls, dropout rises, and the estimand changes. A cross-trial lead built on a phase 2 estimate is not a finding, and the trial that would convert it into one has published nothing.

The mass difference matters for a separate and entirely practical reason. At 4,731.0 g/mol retatrutide sits 82 daltons below tirzepatide — a gap a mass spectrometer resolves instantly and an HPLC purity figure does not address at all.

Which retatrutide figures can be attributed to a TRIUMPH trial?

None. No TRIUMPH trial has published a result, so no weight-loss percentage, no adverse-event rate, no discontinuation figure and no durability figure can be attributed to any of them. The 24.2% figure is phase 2 (n=338, 48 weeks), the 28% at 80 weeks figure is press reporting of a company statement from May 2026 that we could not verify against a primary source, and the 30.3% at 104 weeks figure has no source we could find at all.

How does an unpublished programme compare with published rivals?

Retatrutide's −24.2% leads the field on paper and is the only phase 2 entry in it. Tirzepatide reached −20.9% in SURMOUNT-1 (n=2,539, 72 weeks), CagriSema −20.4% in REDEFINE-1 (n=3,417), mazdutide −16.65% in GLORY-2, semaglutide −14.9% in STEP-1 (n=1,961) and survodutide −13.0% in SYNCHRONIZE-1 — every one of them a phase 3 trial enrolling between 461 and 3,417 participants. Cross-trial comparison is not head-to-head, and phase 2 estimates routinely shrink.

Read that table with its confounds visible, because placing trial numbers side by side is not a comparison. The populations differ, the durations run from 48 to 76 weeks, the estimands differ, and placebo responses differ enough to distort the picture on their own — survodutide's placebo arm lost 5.4% against retatrutide's 2.1%, which compresses one placebo-adjusted effect and inflates another.

The single most consequential unknown is not on the table at all. The discontinuation rate at effective doses is not reported in the phase 2 abstract, and glucagon receptor agonism adds nausea and vomiting risk on top of an already emetogenic class. For scale, tirzepatide's discontinuation for adverse events ran 4.3%, 7.1% and 6.2% across doses against 2.6% on placebo, and semaglutide's gastrointestinal discontinuation ran 4.5% in STEP 1. Every drug in this class shows its tolerability problem at scale, not in a 338-person study — which is one of the things a 5,800-participant programme exists to reveal. See retatrutide side effects for the adverse-event picture as reported so far.

What does the programme's silence mean for buying retatrutide now?

Retatrutide is not approved anywhere we could verify and cannot be legally compounded — it has never been approved, so it has never been in shortage, so no compounding pathway has ever existed for it. It is absent from FDA's drug application database and from FDA's novel approvals lists for 2025 (46 drugs) and 2026 (30 drugs, current through 5 August 2026). Meanwhile this platform holds 1,150 independent lab tests of it — the largest such dataset here, for a drug with one published trial.

Those figures exclude shipping, taxes and customs, coupon codes, bulk tiers, multi-vial kits and account-gated pricing. Peptigrity tracks 530 shops and 11,852 independent lab tests across 118 peptides, with 1,283 community reviews (verified August 2026), and trust scores weight community reviews and independently verified HPLC purity equally at 50% each, with no financial relationship influencing the ranking.

Stop and consider the shape of that. Eleven hundred and fifty independent lab tests of a drug that no regulator has approved anywhere and whose phase 3 programme has published nothing. The supply chain is better characterised than the medicine, and purity data has quietly become a substitute for clinical evidence in how this compound is discussed. High-quality manufacture of a molecule with 338 people of phase 2 data behind it is high-quality manufacture of a molecule with 338 people of data behind it.

That last row is specific to this compound and this moment, and it costs nothing to check — see why 10 mg isn't 10 mg for the purity-versus-quantity distinction, where to buy retatrutide for the full walkthrough, and the retatrutide compound page, retatrutide price data, Purity Index and lab test database for the underlying figures.

Three further points bear on buying while the programme is silent. One legitimate non-trial route exists and it does not run through a shop: ClinicalTrials.gov carries NCT07629401, "Pre-approval Expanded Access of Retatrutide," with status AVAILABLE, operating through physicians and the sponsor — see do you need a prescription for retatrutide and compounding pharmacy versus research peptide. On sport, retatrutide is not named on the WADA 2026 Prohibited List, but the S0 catch-all prohibits substances "with no current approval by any governmental regulatory health authority for human therapeutic use," expressly including "drugs under pre-clinical or clinical development" — on the plain text that captures retatrutide, though that is our reading rather than a published WADA ruling. And one peer-reviewed paper looks directly at what is being sold: Piatkowski, Craven, Cornell & Ferris, "Composition and Labelling Accuracy of Products Sold as Retatrutide in Australia," Drug and Alcohol Review, September 2026, DOI 10.1111/dar.70231 — we verified the citation and could not obtain the abstract, so we are not characterising what it concludes, but it is the closest peer-reviewed analogue to what this platform does.

The trial that would settle this

Every open retatrutide question maps to a registered trial, and not one of those trials has published. Weight-loss efficacy at phase 3 scale sits with TRIUMPH-1 and TRIUMPH-2, sleep apnoea and osteoarthritis with their nested protocols and TRIUMPH-4, the cardiovascular population with TRIUMPH-3, hard cardiovascular and kidney events with NCT06383390, and superiority over tirzepatide with NCT06662383. The one question with no registered answer is the tolerability figure the phase 2 abstract omitted.

Frequently Asked Questions

Has any TRIUMPH trial published results?

No. All four registrational trials are described in a January 2026 design paper by Giblin et al. and none has published a result. As of 11 August 2026 PubMed contains no phase 3 retatrutide results paper of any kind.

Does the 24.2% figure come from TRIUMPH-1?

No. It comes from a phase 2 trial published in the New England Journal of Medicine in 2023 — 338 participants, 48 weeks, 12 mg dose, double-blind and placebo-controlled. Attributing it to a phase 3 TRIUMPH trial is the single most common error in retatrutide coverage, and this site made it before correcting it.

How many people are in the TRIUMPH programme?

More than 5,800 across the four registrational trials, according to the design paper. That figure is reported as a programme total rather than trial by trial, so per-trial enrolment is not something we can quote without inventing it.

What is the head-to-head against tirzepatide, and when will it report?

NCT06662383 is a registered head-to-head trial of retatrutide against tirzepatide, listed as active and not recruiting, with no published results. Our sources give no readout date. Until it reports, "retatrutide beats tirzepatide" compares a 338-person phase 2 result with a 2,539-person phase 3 one.

Is there a cardiovascular outcomes trial?

Yes — NCT06383390, a cardiovascular and kidney outcomes trial, active and not recruiting, with no published results. Outcomes trials measure events rather than weight, which is what produced semaglutide's hazard ratio of 0.80 in SELECT across 17,604 patients.

Can I get retatrutide while the programme is running?

Not through a vendor lawfully. Retatrutide is not approved anywhere we could verify and has never been in shortage, so no compounding route has ever existed. A pre-approval expanded access programme, NCT07629401, is listed as AVAILABLE and runs through physicians and the sponsor rather than through shops.

Where this leaves the programme

TRIUMPH is the trial programme built to confirm the most striking phase 2 result in obesity medicine, and three years after that result appeared it has published nothing. Four registrational trials, more than 5,800 participants, two further registered trials covering hard outcomes and a head-to-head, and zero results papers. Everything anyone knows about retatrutide's efficacy still rests on 338 people over 48 weeks.

That makes this an unusually easy compound to describe accurately and an unusually easy one to describe wrongly. The accurate version is a map: each question has a trial attached, each trial is registered, and none has reported. The wrong version attaches a phase 3 label to a phase 2 number, or an 80-week duration to a 48-week trial, and it is currently the more common of the two.

Browse the weight loss and metabolic peptides category, or our complete peptide guide with 118 compounds (verified August 2026). For per-injection volume, use the retatrutide calculator alongside the reconstitution calculator. Compare shops through independent lab tests and community-verified shop reviews.

This article is for educational and informational purposes only and does not constitute medical advice. Peptides discussed may be investigational compounds not approved by the FDA (or equivalent regulators in your jurisdiction) for human use. Always consult a qualified healthcare provider before using any peptide or research compound. Peptigrity is an independent review platform and does not sell, endorse, or recommend specific products or vendors.